Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Second Law of Thermodynamics02:49

Second Law of Thermodynamics

27.2K
In the quest to identify a property that may reliably predict the spontaneity of a process, a promising candidate has been identified: entropy. Processes that involve an increase in entropy of the system (ΔS > 0) are very often spontaneous; however, examples to the contrary are plentiful. By expanding consideration of entropy changes to include the surroundings, a significant conclusion regarding the relation between this property and spontaneity may be reached. In thermodynamic models, the...
27.2K
Second Law of Thermodynamics00:53

Second Law of Thermodynamics

69.2K
The Second Law of Thermodynamics states that entropy, or the amount of disorder in a system, increases each time energy is transferred or transformed. Each energy transfer results in a certain amount of energy that is lost—usually in the form of heat—that increases the disorder of the surroundings. This can also be demonstrated in a classic food web. Herbivores harvest chemical energy from plants and release heat and carbon dioxide into the environment. Carnivores harvest the...
69.2K
Entropy02:39

Entropy

36.7K
Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
36.7K
Entropy01:18

Entropy

3.7K
The first law of thermodynamics is quantitatively formulated via an equation relating the internal energy of a system, the heat exchanged by it, and the work done on it. A quantitative formulation of the second law of thermodynamics leads to defining a state function, the entropy.
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
3.7K
Stability of Equilibrium Configuration01:23

Stability of Equilibrium Configuration

830
Understanding the stability of equilibrium configurations is a fundamental part of mechanical engineering. In any system, there are three distinct types of equilibrium: stable, neutral, and unstable.
A stable equilibrium occurs when a system tends to return to its original position when given a small displacement, and the potential energy is at its minimum. An example of a stable equilibrium is when a cantilever beam is fixed at one end and a weight is attached to the other end. If the weight...
830
Energy Diagrams - II01:10

Energy Diagrams - II

14.1K
Energy diagrams are important to understand the dynamics of a system. The topology of an energy diagram helps illustrate the equilibrium points of the system.
The point in the energy diagram at which the system’s potential energy is the lowest is known as the local minima. The system tends to stay in this position indefinitely unless acted upon by a net force. The slope of the potential energy diagram at the local minima is zero, indicating that zero net force is acting on the system. The...
14.1K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Realizing Unitary k-Designs with a Single Quench.

Physical review letters·2026
Same author

The space of transport coefficients allowed by causality.

Nature physics·2024
Same author

Mitigation of TDP-43 toxic phenotype by an RGNEF fragment in amyotrophic lateral sclerosis models.

Brain : a journal of neurology·2024
Same author

Rigorous Bounds on Transport from Causality.

Physical review letters·2023
Same author

Undergraduate Teaching During COVID-19.

Applied biosafety : journal of the American Biological Safety Association·2023
Same author

Hydrodynamic Gradient Expansion Diverges beyond Bjorken Flow.

Physical review letters·2022

Related Experiment Video

Updated: Feb 19, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
11:03

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids

Published on: December 4, 2017

9.1K

Universal Spatial Structure of Nonequilibrium Steady States.

Julian Sonner1, Benjamin Withers1

  • 1Department of Theoretical Physics, University of Geneva, 24 quai Ernest-Ansermet, 1214 Genève 4, Switzerland.

Physical Review Letters
|November 4, 2017
PubMed
Summary

We identified universal spatial structures in forced flows over obstacles, characterized by collective modes. These modes offer a new way to measure the viscosity over entropy density ratio and reveal novel nonequilibrium phase transitions.

More Related Videos

Generation and Coherent Control of Pulsed Quantum Frequency Combs
06:42

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

9.8K
Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
11:00

Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section

Published on: July 19, 2016

12.0K

Related Experiment Videos

Last Updated: Feb 19, 2026

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
11:03

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids

Published on: December 4, 2017

9.1K
Generation and Coherent Control of Pulsed Quantum Frequency Combs
06:42

Generation and Coherent Control of Pulsed Quantum Frequency Combs

Published on: June 8, 2018

9.8K
Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
11:00

Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section

Published on: July 19, 2016

12.0K

Area of Science:

  • Condensed Matter Physics
  • Fluid Dynamics
  • Statistical Mechanics

Background:

  • Nonequilibrium steady states (NESS) are crucial for understanding systems driven far from equilibrium.
  • Forced flows over obstacles present complex fluid dynamics with emergent spatial structures.

Purpose of the Study:

  • To characterize the universal spatial structure of NESS in forced flows over obstacles.
  • To define and analyze collective modes governing these structures.
  • To explore potential new routes for measuring material properties and identifying phase transitions.

Main Methods:

  • Analysis of collective modes in strongly coupled many-body systems.
  • Holographic duality to connect spatial modes with quasinormal modes.
  • Investigation of hydrodynamic and non-hydrodynamic mode contributions.

Main Results:

  • Universal spatial structures emerge at large distances from obstacles.
  • Collective modes, analogous to quasinormal modes, quantitatively describe these structures.
  • Hydrodynamic mode decay lengths are linked to the shear viscosity over entropy density ratio (η/s).
  • A new class of nonequilibrium phase transitions is identified.

Conclusions:

  • Collective modes provide a framework for understanding universal NESS properties.
  • The study suggests a novel experimental method for measuring η/s.
  • The identified phase transitions highlight complex emergent behavior in driven systems.